Manta rays are perhaps some of the most unique marine vertebrates in existence. With their diamond-like shape and their large wing-shaped fins, they very much evoke feelings of awe and serenity when observed moving through the open ocean. Despite their gentle nature and their beauty, manta ray populations have been sharply dropping in the last few decades. According to the IUCN, certain subpopulations of the giant manta ray (Manta birostris) have been depleted by 80% due to overfishing. These populations, located largely within the Indo-Pacific and the Caribbean, are exploited for their gill plates and their meat. In the Chinese province of Guangzhou, the manta gill plate trade is estimated at almost $30 million a year. These plates, located just behind the ray’s mouth, help filter out plankton and other food from the surrounding water. In traditional Chinese culture, the plates are used to treat a variety of illnesses from cancer to chickenpox. No scientific evidence points to manta gill plates’ effectiveness in treating these conditions.
Luckily, a few nations are stepping up to prevent the harvesting of giant manta rays for their meat or gill plates. Peru recently became the twelfth country to ban manta fishing, joining Ecuador, the Maldives, and New Zealand in establishing protective measures for these gentle giants. Though harvesting Manta birostris is illegal in Mexico, enforcement is suspect and the population off the coast of Mexico is believed to remain in steady decline. Manta rays are also commonly unintentionally tangled in fishing gear, an issue that Peru hopes to address by requiring all tangled rays to be released immediately by the fishing vessels responsible for the catch. The protective measures from Peru are important not only because the nation’s waters boasts the largest known population of giant manta rays, but also because this population is known to migrate between Peru and Ecuador. With Ecuador having previously established a fishing ban on the giant manta ray, these two nations have now effectively protected most of if not the entire geographic range of this population.
Manta rays are long-lived animals that only give birth to one pup every two to five years. Therefore, it may take some time for the populations surrounding South America to rebound from historical fishing pressure. According to WildAid, an international nonprofit focused on protecting the giant manta ray, the next countries targeted for protective legislation are Sri Lanka and India. Additionally, the organization is calling for conservation measures that protect the endangered mobula ray, Mobula mobular (which is also hunted for its meat and gill plates). Though it remains an uphill battle, it’s good to know that a few critical nations are stepping up and making efforts to protect these ancient and majestic marine animals.
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